Hypocalcaemia, Hypoglycaemia, Macrosomia and Congenital Cryptorchidism in a Male Offspring of a Mother with Overweight and Gestational Diabetes Mellitus

This paper reports a case of a male infant born to a 32-year-old multiparous mother with overweight (BMI 28.5kg/m2) and gestational diabetes mellitus (GDM). The mother had fasting hyperglycaemia (range 5.7- 6.0mmol/L) noted at 24 weeks of pregnancy and was managed with diet alone. There is no family history of diabetes mellitus and the mother did not have pre-eclampsia. Physical examination of the infant revealed macrosomia (birthweight, 4600g) and bilateral congenital cryptorchidism. The baby suffered severe hypoglycaemia (blood glucose 1.7mmol/L) and hypocalcaemia (total serum calcium 1.03mmol/L), manifesting with seizures. He was successfully managed with 10% dextrose water and calcium gluconate infusion, using standard protocol. His karyotype is 46 XY. The patient was discharged from admission at the age of 10 days and was referred to the paediatric endocrinologist at the tertiary hospital. By 8 weeks of age, the right testis was noticed to have descended into the right scrotum. At the age of 3 months, the left testis was still not palpable either in the inguinal canal or the scrotal sac. The patient was lost to follow up. Conclusion: Diet-treated maternal overweight in association with GDM could potentially increase the risk for hypocalcaemia, hypoglycaemia, macrosomia and congenital cryptorchidism in the offspring, highlighting the need for physicians to assess for the presence of these morbidities in such infants.

The offspring of gestational diabetes

Gestational diabetes mellitus (GDM) usually develops in the second half of pregnancy and, in order to address the impact of GDM on the conceptus, several issues must be raised: what are the immediate implications for the fetus and the neonate and why do they happen? What are the consequences for the offspring? What can be done? In a theoretical model the whole pathogenesis and spectrum of fetal and neonatal mortality and morbidity could primarily be attributed to the excessive transferal of glucose from mother of fetus, inducing fetal hyperglycemia, leading to fetal pancreatic islet hypertrophy and beta-cell hyperplasia with a consequent rise in insulin secretion. However, besides, and in addition to glucose, it is quite possible that other metabolic fuels, from amino acids to lipids, may also cross the placenta further contributing to the adverse intrauterine environment. Depending upon the time of gestation during critical developmental stages, the same metabolic fuels would have different effects upon the fetus, the neonate and quite possibly, upon the long-term outcome from neurological and psychosocial impairment to the adult development of metabolic and cardiovascular disorders. Based on clinical and experimental evidence that poor maternal homeostasis is at the core of the problem, it is of paramount importance to identify women at risk of GDM and to keep a tight metabolic control in order to avoid immediate and long-term consequences for their offspring.